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Scope Mount Receiver Drill Tap Fixture

Joined
Feb 17, 2012
Location
Michigan, USA
I was hoping someone could guide me in the general direction for building my own scope mount jig for drilling and tapping, or recommend another model. The link below shows a great example which is no longer available. The most crucial aspect of mounting a scope, besides not drilling into the chamber, is making sure your mount is properly aligned. Scope is worthless if the mount(s) isn't aligned properly.


Scope Mount Receiver Drill Tap Fixture #31 Drill 6-48 Tap

Thanks in advance,

Matt
 
I was hoping someone could guide me in the general direction for building my own scope mount jig for drilling and tapping, or recommend another model. The link below shows a great example which is no longer available. The most crucial aspect of mounting a scope, besides not drilling into the chamber, is making sure your mount is properly aligned. Scope is worthless if the mount(s) isn't aligned properly.


Scope Mount Receiver Drill Tap Fixture #31 Drill 6-48 Tap

Thanks in advance,

Matt

Well Matt they don't make that anymore because it did not work. People make a new one of those every 10 years or so and sell a few and then run and hide where people can't find them and beet them up. They align the holes to the inside of the receiver bore. Most of the time the receiver bore is pointed no where in the same direction as the barrel.

You have to use some sort of fixture that lines the holes up to the barrel. That will take care of your side to side alignment. Then you simply rely on the scope bases to give you the proper height alignment.

The Forester Site Jig has always sort of been the industry standard for what works and is reliable. If you want to make one by all means study the Forester and copy it. Improve it where you see fit. I think you will find that it's pretty hard to make one for the $700.00 that they charge for them. If you charge $100.00 labor for each drill and tap job it will pay for itself in the first 7 jobs. The next 40 years is pure profit.

I looked at making a long version of the Forester a few years back and I gave up on the idea because the block of aluminum needed was going to cost me about $300 to $400 dollars alone. When faced with barrels to long for the Forester, muzzle loaders and such I dial in two V Blocks on the mill and use the machine as one great big Forester jig. It only takes 10 minutes to set up the V blocks and I only do one or two over length barrels a year.

If you do make one I would make it about 36 inches long. The standard one is 20 and is fine for hunting rifles but gets touch and go with shotguns and you can't do muzzle stuffers in one setup.

ADD NOTE: I was just at metal supermarket and they quoted me $240.00 for a 4x4x36 block. So its not as bad as I thought. I'm still not going to make one.

I looked up the price and they only want $478.00 for the jig and one set of bushings. You can make the rest of the bushings for free from drill rod.

http://www.forsterproducts.com/catalog.asp?prodid=701233
 
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The Forester Site Jig has always sort of been the industry standard for what works and is reliable. If you want to make one by all means study the Forrester and copy it. Improve it where you see fit. I think you will find that it pretty hard to make one for the $700.00 that they charge for them. If you charge $100.00 labor for each drill and tap job it will pay for itself in the first 7 jobs. The next 40 years is pure profit.

Agreed 100%.
I've had my Forster for _OVER_ 20 years.
:eek: I just realized that I bought it in 1989...

And, for what it's worth, I do the exact same thing with the
v-blocks, save that I made a set that keys into my Bridgeport's table.
 
Agreed 100%.
I've had my Forster for _OVER_ 20 years.
:eek: I just realized that I bought it in 1989...

And, for what it's worth, I do the exact same thing with the
v-blocks, save that I made a set that keys into my Bridgeport's table.

Yeah well having them just drop right into the table slots all pre-aligned is cheaterering! Where is you spirit of adventure? I actually think about doing that every time I do one. But then I just do the job and the urge pass's. The power of positive procrastination.
 
Yeah well having them just drop right into the table slots all pre-aligned is cheaterering! Where is you spirit of adventure? I actually think about doing that every time I do one. But then I just do the job and the urge pass's. The power of positive procrastination.

Ha!
It must have taken me at LEAST 5 years to get around to doing it. :D
Even then, I only did it because I was doing some fixture keys and did them at the same time. :D
 
matt
i have a forster that i no longer use with 6,8,10 bushings i want 300.00 + shipping for it pm me if interested. contact me only if you are sure you want it. thanks batw
 
Forster Universal Sight Mounting Fixture

matt
i have a forster that i no longer use with 6,8,10 bushings i want 300.00 + shipping for it pm me if interested. contact me only if you are sure you want it. thanks batw

I was doing a web search for this item, and this thread came up.

If you're willing to sell it, I would be interested at that price.

Thanks
 
The Forster system looks handy but if you use the machined edge to dial in the fixture, aren't you relying on the OD of the barrel being in the same alignment as the bore??
My inclination is to first level the action then , using an indicator rod in the muzzle and dial it in to my x axis. If the barrel is removed, I'd use a similar setup with an indicator rod (or reamer mandrel) and pilot bushings to get my alignment.
The fixture can still be used in this way and will help speed up the drilling and tapping process.
Tell me if I'm being too anal.
JB
 
Well if you happen to be a hobbyist then anything goes. If you pay rent, wages, phone, power and heat then its a little bit different.
About the most you can charge for drill and tap is $25 per hole or $100.00 for the job plus parts. No one will pay more than that and every kook in his garage charges $50.00. You get $100.00 because you don't wreak his gun and he can have it back and go hunting in 2 days not 6 months. Money dictates how much time you can spend on a job before it is not worth doing.
You will probably waste a 1/2 hour to 3/4 of an hour booking the gun in and out. If your hourly rate for man and machine is $100 per hour that leaves you 15 minutes to 1/2 hour to disassemble the gun, drill and tap and reassemble the gun. Be as anal as you want but if you can't justify your existence and provide at least $250.00 in received labor per day to the owner every day you will find yourself fired.

If you work for yourself and you cant make rent, power, phone, computer, heat, bank charges, commissaries like trash and snow removal, consumable tooling, new tooling, wages AND NET PROFIT, so that you can retire some day, you will go broke.

If you were working for me, you would use the forester jig, or I would fire you and give you the number of my competition. Or, if I could not afford to loose you, I would no longer offer drill and tap. Very simple mathematics. LOL
 
Ha, Ha...Damn now you've got me depressed about my chances of retirement...
....on the bright side, I don't have snow removal to worry about down here!

I didn't mention that I charge extra if they want the job done with "love". LOL.

JB
 
Actually before you screw up a gun. Give this a think. You want to drill and tap the barrel so that the holes line up to the inside. You can do that. But your sight is going to be sitting off center on the outside so it will be drastically tipped to one side. It will look like hell and the customer will freak out on you. Center the sight to the outside so it sits up straight and its in the middle of the barrel. Sights are adjustable from side to side for a reason. It has to work but it has to look good too. Its not your fault the barrel maker put the hole off to one side. Dontchaknow!

Gunsmith Rod Henrickson Sight.jpg
 
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I know that I am resurrecting a very old thread but the subject matter is in inline with my question and the previous posts give lots of information. I also did a search and did find anything more current.

I have several rifles that I am working on and will need to mount scopes. A forster jig is not cost effective to buy for just a couple of mounts. Using V blocks on a mill is a solution that according to the above posts is time consuming to set up.

Why couldn't you mount the rifle between centers on a lathe and make a fixture to fit in a qctp with the correct spacing for the scope mounts. Something like the crude sketch below. You would need a long center to fit through the action up to the chamber on the barrel and probably something to fit up against the base of the receiver to hold it square. This seems like it would a lot easier to do than aligning V blocks on a mill and having to lay out the hole spacing.

Am I missing something here?
 

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You'll have to figure a way to clamp that all in place.

I currently have the forster jig, but have set up several in a mill using a mandrel in the reciever and dialing it in straight. Then if you have a DRO it's fairly quick to punch and tap the holes perfectly.
 
I know that I am resurrecting a very old thread but the subject matter is in inline with my question and the previous posts give lots of information. I also did a search and did find anything more current.

I have several rifles that I am working on and will need to mount scopes. A forster jig is not cost effective to buy for just a couple of mounts. Using V blocks on a mill is a solution that according to the above posts is time consuming to set up.

Why couldn't you mount the rifle between centers on a lathe and make a fixture to fit in a qctp with the correct spacing for the scope mounts. Something like the crude sketch below. You would need a long center to fit through the action up to the chamber on the barrel and probably something to fit up against the base of the receiver to hold it square. This seems like it would a lot easier to do than aligning V blocks on a mill and having to lay out the hole spacing.

Am I missing something here?
A little fussy raising and lowering the qctp to get the mount centered, but I do not see why it would not work.
I have done a couple of my own rifles by just holding the receiver in a vice on the mill, did not realize the possible bad out comes that could have happened. Mine did come out OK.
 
I don't think that getting it centered will be a big deal. I will scribe a line on the fixture at the centerline of the holes. With the barrel being held between centers and knowing the distance from the base on the qctp to centerline on the lathe it should be easy to get the fixture centered. See the sketch below for my current thoughts on the fixture that I would mount in a tool holder for the qctp.
 

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